The present invention relates to enhancing the production of hydrocarbons from a subterranean formation. More particularly, the invention relates to formation conditioning fluids comprising peroxide generating compounds and their methods of use relative to enhancing the placement and performance of consolidating agents in subterranean formations.
Hydrocarbon wells are often located in subterranean formations that contain unconsolidated particulates (e.g., sand, gravel, proppant, fines, etc.) that may migrate out of the subterranean formation with the oil, gas, water, and/or other fluids produced by the wells. The presence of such particulates in produced fluids is undesirable in that the particulates may abrade pumping and other producing equipment and/or reduce the production of desired fluids from the well. Moreover, particulates that have migrated into a well bore (e.g., inside the casing and/or perforations in a cased hole), among other things, may clog portions of the well bore, hindering the production of desired fluids from the well. The term “unconsolidated particulates,” and derivatives thereof, is defined herein to include loose particulates and particulates bonded with insufficient bond strength to withstand the forces created by the production of fluids through the formation.
Unconsolidated particulates may comprise, among other things, sand, gravel, fines and/or proppant particulates in the subterranean formation, for example, proppant particulates placed in the subterranean formation in the course of a fracturing or gravel-packing operation. The terms “unconsolidated subterranean formations,” “unconsolidated portions of a subterranean formation,” and derivatives thereof are defined herein to include any formations that contain unconsolidated particulates, as that term is defined herein.
One method used to control particulates in unconsolidated formations involves consolidating unconsolidated particulates into stable, permeable masses by applying a consolidating agent (e.g., a resin or tackifying agent) to a portion of the subterranean formation. The application of such resins or tackifying agents is often referred to as a consolidation treatment. One problem that may be experienced in such consolidation treatments is the failure of the resin or tackifying agent to adhere to the rock surfaces of the formation. This failure may be due to the presence of oil, condensates, or other debris (collectively referred to herein as “contaminants”) on the rock surfaces.
To combat this contaminants problem, oftentimes the formation may be pretreated with a mutual solvent prior to the consolidation treatment in an attempt to remove the oil and/or the debris and prepare the surface of the formation rock in the formation to allow the resin or tackifier to adhere to its surface. Glycol ethers are an example of the type of solvent that may be used in such pre-treatments. The use of such solvents is very expensive because high concentrations of the solvent are necessary to achieve any sort of contaminant reduction. For example, it is often recommended that solutions comprising about 50% to about 100% of the solvent be used in relatively large pre-treatments. Additionally, many of these solvents present toxicity and handling concerns.